“Catalytic Engine” NOx Reduction of Diesel Engines with New Concept Onboard Ammonia Synthesis System

1992 ◽  
Author(s):  
Toshio Nakahira ◽  
Kinji Tsujimura ◽  
Toshiaki Kakegawa ◽  
Ken-ichi Aika ◽  
Masaaki Takiguchi ◽  
...  
Keyword(s):  
Diesel Engines ◽  
Ammonia Synthesis ◽  
Nox Reduction ◽  
Synthesis System

NOx Reduction Strategies for DI Diesel Engines

1992 ◽  
Author(s):  
Peter L. Herzog ◽  
Ludwig Bürgler ◽  
Ernst Winklhofer ◽  
Paul Zelenka ◽  
Wolfgang Cartellieri
Keyword(s):  
Diesel Engines ◽  
Nox Reduction ◽  
Reduction Strategies

scholarly journals Perovskite-Based Catalysts as Efficient, Durable, and Economical NOx Storage and Reduction Systems

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 208
Author(s):  
Jon A. Onrubia-Calvo ◽  
Beñat Pereda-Ayo ◽  
Juan R. González-Velasco
Keyword(s):  
Removal Efficiency ◽  
Diesel Engines ◽  
Nox Reduction ◽  
Platinum Group Metals ◽  
Nox Storage ◽  
Automotive Application ◽  
Nox Removal ◽  
Nox Storage And Reduction ◽  
Nox Storage Capacity ◽  
Nox Removal Efficiency

Diesel engines operate under net oxidizing environment favoring lower fuel consumption and CO2 emissions than stoichiometric gasoline engines. However, NOx reduction and soot removal is still a technological challenge under such oxygen-rich conditions. Currently, NOx storage and reduction (NSR), also known as lean NOx trap (LNT), selective catalytic reduction (SCR), and hybrid NSR–SCR technologies are considered the most efficient control after treatment systems to remove NOx emission in diesel engines. However, NSR formulation requires high platinum group metals (PGMs) loads to achieve high NOx removal efficiency. This requisite increases the cost and reduces the hydrothermal stability of the catalyst. Recently, perovskites-type oxides (ABO3) have gained special attention as an efficient, economical, and thermally more stable alternative to PGM-based formulations in heterogeneous catalysis. Herein, this paper overviews the potential of perovskite-based formulations to reduce NOx from diesel engine exhaust gases throughout single-NSR and combined NSR–SCR technologies. In detail, the effect of the synthesis method and chemical composition over NO-to-NO2 conversion, NOx storage capacity, and NOx reduction efficiency is addressed. Furthermore, the NOx removal efficiency of optimal developed formulations is compared with respect to the current NSR model catalyst (1–1.5 wt % Pt–10–15 wt % BaO/Al2O3) in the absence and presence of SO2 and H2O in the feed stream, as occurs in the real automotive application. Main conclusions are finally summarized and future challenges highlighted.

Sign in / Sign up

Export Citation Format

Share Document